From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with ESMTP id 590846B002D for ; Mon, 21 Nov 2011 09:18:05 -0500 (EST) Date: Mon, 21 Nov 2011 15:17:59 +0100 From: Andi Kleen Subject: Re: [PATCH 5/8] readahead: add /debug/readahead/stats Message-ID: <20111121141759.GE24062@one.firstfloor.org> References: <20111121091819.394895091@intel.com> <20111121093846.636765408@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20111121093846.636765408@intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Wu Fengguang Cc: Andrew Morton , Linux Memory Management List , linux-fsdevel@vger.kernel.org, Ingo Molnar , Jens Axboe , Peter Zijlstra , Rik van Riel , LKML , Andi Kleen > +static unsigned long ra_stats[RA_PATTERN_MAX][RA_ACCOUNT_MAX]; Why not make it per cpu? That should get the overhead down, probably even enough that it can be enabled by default. BTW I have an older framework to make it really easy to add per cpu stats counters to debugfs. Will repost, that would simplify it even more. -Andi -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org